Each vessel's two MaK 12M551AK engines produce 11,860 HP, which provides a maximum service speed of 20.5 knots (38.0 km/h; 23.6 mph).

It was originally designed to carry only overheight (truck) traffic but in 1984, an upper car deck was installed for 150 non-overheight vehicles.

From engine work to major modifications and improvements, the vessels were refitted to provide an additional 20 years of service.

In July 2018, BC Ferries announced that it had issued a request for proposals to build replacement vessels for all C-class ships, with deliveries beginning in 2024.

[2] In 2022, BC Ferries deferred the replacement after it was determined the vessels could be given five-year life extensions beyond their original planned retirement dates.

On August 9, 1979, Queen of Alberni was transiting through Active Pass when it ran aground on Galiano Island, tipping fifteen degrees to starboard.

On October 19, 1980, Queen of Coquitlam tipped over and landed on her side in the Burrard Shipyards drydock during a maintenance layover, causing approximately CA$3 million in damage.

On December 15, 2001, Queen of Alberni got caught in a heavy wind storm which turned a regular 2-hour crossing into a 71⁄2-hour ordeal.

After the captain gave ample warning, the ship coasted into the nearby Sewell's Marina, where it overran more than a dozen boats before running aground.